Hormonal induction of Dopa decarboxylase in the epidermis of Drosophila is mediated by the Broad-Complex

Development ◽  
1995 ◽  
Vol 121 (11) ◽  
pp. 3913-3922 ◽  
Author(s):  
R.B. Hodgetts ◽  
W.C. Clark ◽  
S.L. O'Keefe ◽  
M. Schouls ◽  
K. Crossgrove ◽  
...  
Keyword(s):  
Consensus Sequence ◽  
Regulatory Region ◽  
Early Gene ◽  
Dopa Decarboxylase ◽  
Specific Response ◽  
Consensus Binding Site ◽  
The Central Nervous System ◽  
Broad Complex ◽  
Early Puff ◽  
Third Instar Larvae

The 2B5 early puff locus corresponds to the Broad-Complex BR-C) and encodes a family of transcription factors whose members are induced by the molting hormone ecdysone. Mutations in the br subcomplementation group substantially reduce the levels of Dopa decarboxylase (DDC) in the epidermis of mature third instar larvae but not in mature second instar organisms. Enzyme levels are normal in the central nervous system of the two mutants examined. The specificity of these effects suggests that a product of the BR-C locus mediates the rapid appearance of DDC in mature third instar larvae experiencing an elevated titer of ecdysone. The likely identity of this protein has been confirmed by pursuing the observation that the br28 allele caused by the insertion of a Pelement into the Z2 DNA-binding domain. Both the transcript and a protein carrying this domain are present in the epidermis and a BR-C recombinant protein carrying the Z2 finger binds to the first intron of the Ddc gene. Five binding sites have been identified within the intron by DNAase I footprinting and a core consensus sequence has been derived which shares some identity with the consensus binding site of the Z2 protein to the Sgs-4 regulatory region. Our demonstration that Ddc is a target of BR-C in the epidermis is the first direct evidence of a role for this early gene in a tissue other than the salivary glands. The data reinforce the idea that BR-C, which clearly mediates a salivary gland-specific response to ecdysone, may play a widespread role in the hormone's activation of gene cascades in other target tissues.

Short repeated elements in the upstream regulatory region of the SUC2 gene of Saccharomyces cerevisiae

1986 ◽  
Vol 6 (7) ◽  
pp. 2324-2333
Author(s):  
L Sarokin ◽  
M Carlson
Keyword(s):  
Carbon Catabolite Repression ◽  
Consensus Sequence ◽  
Regulatory Region ◽  
Lacz Fusion ◽  
Upstream Region ◽  
Upstream Regulatory Region ◽  
Heterologous Promoter ◽  
Suc2 Gene ◽  
High Level ◽  
Repeated Motif

Expression of secreted invertase from the SUC2 gene is regulated by carbon catabolite repression. Previously, an upstream regulatory region that is required for derepression of secreted invertase was identified and shown to confer glucose-repressible expression to the heterologous promoter of a LEU2-lacZ fusion. In this paper we show that tandem copies of a 32-base pair (bp) sequence from the upstream regulatory region activate expression of the same LEU2-lacZ fusion. The level of expression increased with the number of copies of the element, but was independent of their orientation; the expression from constructions containing four copies of the sequence was only twofold lower than that when the entire SUC2 upstream regulatory region was present. This activation was not significantly glucose repressible. The 32-bp sequence includes a 7-bp motif with the consensus sequence (A/C)(A/G)GAAAT that is repeated at five sites within the upstream regulatory region. Genetic evidence supporting the functional significance of this repeated motif was obtained by pseudoreversion of a SUC2 deletion mutant lacking part of the upstream region, including two copies of the 7-bp element. In three of five pseudorevertants, the mutations that restored high-level SUC2 expression altered one of the remaining copies of the 7-bp element.

Repeated CT elements bound by zinc finger proteins control the absolute and relative activities of the two principal human c-myc promoters

1993 ◽  
Vol 13 (9) ◽  
pp. 5710-5724
Author(s):  
E DesJardins ◽  
N Hay
Keyword(s):  
Zinc Finger ◽  
Tandem Repeats ◽  
Zinc Finger Protein ◽  
Consensus Sequence ◽  
Regulatory Region ◽  
Maximal Activity ◽  
Single Copy ◽  
Promoter Usage

Transcription of the human proto-oncogene c-myc is governed by two tandem principal promoters, termed P1 and P2. In general, the downstream promoter, P2, is predominant, which is in contrast to the promoter occlusion phenomenon usually observed in genes containing tandem promoters. A shift in human c-myc promoter usage has been observed in some tumor cells and in certain physiological conditions. However, the mechanisms that regulate promoter usage are not well understood. The present studies identify regulators which are required to promote transcription from both human c-myc promoters, P1 and P2, and have a role in determining their relative activities in vivo. A novel regulatory region located 101 bp upstream of P1 was characterized and contains five tandem repeats of the consensus sequence CCCTCCCC (CT element). The integrity of the region containing all five elements is required to promote transcription from P1 and for maximal activity from P2 in vivo. A single copy of this same element, designated CT-I2, also appears in an inverted orientation 53 bp upstream of the P2 transcription start site. This element has an inhibitory effect on P1 transcription and is required for P2 transcription. The transcription factor Sp1 was identified as the factor that binds specifically to the tandem CT elements upstream of P1 and to the CT-I2 element upstream of P2. In addition, the recently cloned zinc finger protein ZF87, or MAZ, was also able to bind these same elements in vitro. The five tandem CT elements can be functionally replaced by a heterologous enhancer that only in the absence of CT-I2 reverses the promoter usage, similar to what is observed in the translocated c-myc allele of Burkitt's lymphoma cells.

Shear stress induces hepatocyte PAI-1 gene expression through cooperative Sp1/Ets-1 activation of transcription

2006 ◽  
Vol 291 (1) ◽  
pp. G26-G34 ◽  
Author(s):  
Hideki Nakatsuka ◽  
Takaaki Sokabe ◽  
Kimiko Yamamoto ◽  
Yoshinobu Sato ◽  
Katsuyoshi Hatakeyama ◽  
...  
Keyword(s):  
Gene Expression ◽  
Shear Stress ◽  
Consensus Sequence ◽  
Early Gene ◽  
Immediate Early ◽  
Mrna Levels ◽  
Consensus Sequences ◽  
Static Conditions ◽  
Stress Dependent ◽  
Pai 1

Partial hepatectomy causes hemodynamic changes that increase portal blood flow in the remaining lobe, where the expression of immediate-early genes, including plasminogen activator inhibitor-1 (PAI-1), is induced. We hypothesized that a hyperdynamic circulatory state occurring in the remaining lobe induces immediate-early gene expression. In this study, we investigated whether the mechanical force generated by flowing blood, shear stress, induces PAI-1 expression in hepatocytes. When cultured rat hepatocytes were exposed to flow, PAI-1 mRNA levels began to increase within 3 h, peaked at levels significantly higher than the static control levels, and then gradually decreased. The flow-induced PAI-1 expression was shear stress dependent rather than shear rate dependent and accompanied by increased hepatocyte production of PAI-1 protein. Shear stress increased PAI-1 transcription but did not affect PAI-1 mRNA stability. Functional analysis of the 2.1-kb PAI-1 5′-promoter indicated that a 278-bp segment containing transcription factor Sp1 and Ets-1 consensus sequences was critical to the shear stress-dependent increase of PAI-1 transcription. Mutations of both the Sp1 and Ets-1 consensus sequences, but not of either one alone, markedly prevented basal PAI-1 transcription and abolished the response of the PAI-1 promoter to shear stress. EMSA and chromatin immunoprecipitation assays showed binding of Sp1 and Ets-1 to each consensus sequence under static conditions, which increased in response to shear stress. In conclusion, hepatocyte PAI-1 expression is flow sensitive and transcriptionally regulated by shear stress via cooperative interactions between Sp1 and Ets-1.

scholarly journals The variable monoaminergic outcomes of cleaner fish brains when facing different social and mutualistic contexts

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4830 ◽  
Author(s):  
Murilo S. de Abreu ◽  
João P.M. Messias ◽  
Per-Ove Thörnqvist ◽  
Svante Winberg ◽  
Marta C. Soares
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Social Behaviour ◽  
Visual Assessment ◽  
Physical Contact ◽  
Specific Response ◽  
Dopaminergic Activity ◽  
Cleaner Fish ◽  
The Central Nervous System ◽  
The Impact

The monoamines serotonin and dopamine are important neuromodulators present in the central nervous system, known to be active regulators of social behaviour in fish as in other vertebrates. Our aim was to investigate the region-specific brain monoaminergic differences arising when individual cleaners face a client (mutualistic context) compared to when they are introduced to another conspecific (conspecific context), and to understand the relevance of visual assessment compared to the impact of physical contact with any partner. We demonstrated that serotoninergic activity at the diencephalon responds mostly to the absence of physical contact with clients whereas cerebellar dopaminergic activity responds to actual cleaning engagement. We provide first insights on the brain’s monoaminergic (region-specific) response variations, involved in the expression of cleaner fishes’ mutualistic and conspecific behaviour. These results contribute to a better understanding of the monoaminergic activity in accordance to different socio-behavioural contexts.

The gene for the heat-shock protein 70 of Euplotes focardii, an Antarctic psychrophilic ciliate

2004 ◽  
Vol 16 (1) ◽  
pp. 23-28 ◽  
Author(s):  
ANTONIETTA LA TERZA ◽  
CRISTINA MICELI ◽  
PIERANGELO LUPORINI
Keyword(s):  
Thermal Stress ◽  
Heat Shock ◽  
Heat Shock Protein ◽  
Heat Shock Protein 70 ◽  
Regulatory Region ◽  
Regulatory Elements ◽  
Specific Response ◽  
Hsp70 Gene ◽  
Sequence Motifs ◽  
Coding Region

In the Antarctic ciliate, Euplotes focardii, the heat-shock protein 70 (Hsp70) gene does not show any appreciable activation by a thermal stress. Yet, it is activated to appreciable transcriptional levels by oxidative and chemical stresses, thus implying that it evolved a mechanism of selective, stress-specific response. A basic step in investigating this mechanism is the determination of the complete nucleotide sequence of the E. focardii Hsp70 gene. This gene contains a coding region specific for an Hsp70 protein that carries unique amino acid substitutions of potential significance for cold adaptation, and a 5' regulatory region that includes sequence motifs denoting two distinct types of stress-inducible promoters, known as “Heat Shock Elements” (HSE) and “Stress Response Elements” (StRE). From the study of the interactions of these regulatory elements with their specific transactivator factors we expect to shed light on the adaptive modifications that prevent the Hsp70 gene of E. focardii from responding to thermal stress while being responsive to other stresses.

Sequencing and Characterization of the xyl Operon of a Gram-Positive Bacterium, Tetragenococcus halophila

1998 ◽  
Vol 64 (7) ◽  
pp. 2513-2519 ◽  
Author(s):  
Yasuo Takeda ◽  
Kazuma Takase ◽  
Ichiro Yamato ◽  
Keietsu Abe
Keyword(s):  
Consensus Sequence ◽  
Regulatory Gene ◽  
Regulation Of Gene Expression ◽  
Regulatory Region ◽  
Gc Content ◽  
Amino Acid Sequences ◽  
Dependent Manner ◽  
Positive Bacterium ◽  
Gram Positive ◽  
Palindromic Structure

ABSTRACT The xyl operon of a gram-positive bacterium,Tetragenococcus halophila (previously calledPediococcus halophilus), was cloned and sequenced. The DNA was about 7.7 kb long and contained genes for a ribose binding protein and part of a ribose transporter, xylR (a putative regulatory gene), and the xyl operon, along with its regulatory region and transcription termination signal, in this order. The DNA was AT rich, the GC content being 35.8%, consistent with the GC content of this gram-positive bacterium. The xyl operon consisted of three genes, xylA, encoding a xylose isomerase, xylB, encoding a xylulose kinase, andxylE, encoding a xylose transporter, with predicted molecular weights of 49,400, 56,400, and 51,600, respectively. The deduced amino acid sequences of the XylR, XylA, XylB, and XylE proteins were similar to those of the corresponding proteins in other gram-positive and -negative bacteria, the similarities being 37 to 64%. Each polypeptide of XylB and XylE was expressed functionally inEscherichia coli. XylE transported d-xylose in a sodium ion-dependent manner, suggesting that it is the first described xylose/Na+ symporter. The XylR protein contained a consensus sequence for binding catabolites of glucose, such as glucose-6-phosphate, which has been discovered in glucose and fructose kinases in bacteria. Correspondingly, the regulatory region of this operon contained a putative binding site of XylR with a palindromic structure. Furthermore, it contained a consensus sequence, CRE (catabolite-responsive element), for binding CcpA (catabolite control protein A). We speculate that the transcriptional regulation of this operon resembles the regulation of catabolite-repressible operons such as the amy, lev, xyl, andgnt operons in various gram-positive bacteria. We discuss the significance of the regulation of gene expression of this operon inT. halophila.

scholarly journals A novel cis-acting element controlling the rat CYP2D5 gene and requiring cooperativity between C/EBP beta and an Sp1 factor.

1994 ◽  
Vol 14 (2) ◽  
pp. 1383-1394 ◽  
Author(s):  
Y H Lee ◽  
M Yano ◽  
S Y Liu ◽  
E Matsunaga ◽  
P F Johnson ◽  
...  
Keyword(s):  
Transcription Factors ◽  
Ternary Complex ◽  
Sequence Similarity ◽  
Consensus Sequence ◽  
Regulatory Region ◽  
Mrna Levels ◽  
Binding Studies ◽  
Mobility Shift ◽  
Specific Expression ◽  
Nuclear Extracts

The rat CYP2D5 gene encodes a cytochrome P450 and is expressed in liver cells. Its expression commences a few days after birth, and maximal mRNA levels are achieved when animals reach puberty. Transfection and DNA binding studies were performed to investigate the mechanism controlling developmentally programmed, liver-specific expression of CYP2D5. Transfection studies using a series of CYP2D5 upstream DNA chloramphenicol acetyltransferase gene fusion constructs identified a segment of DNA between nucleotides -55 and -156 that conferred transcriptional activity in HepG2 cells. Activity was markedly increased by cotransfection with a vector expressing C/EBP beta but was unaffected by vectors producing other liver-enriched transcription factors (C/EBP alpha, HNF-1 alpha, and DBP). DNase I footprinting revealed a region protected by both HepG2 and liver cell nuclear extracts between nucleotides -83 and -112. This region displayed some sequence similarity to the Sp1 consensus sequence and was able to bind the Sp1 protein, as assessed by a gel mobility shift assay. The role of Sp1 in CYP2D5 transcription was confirmed by trans activation of the 2D5-CAT construct in Drosophila melanogaster cells by using an Sp1 expression vector. C/EBP beta alone was unable to directly bind the -83 to -112 region of the promoter but was able to produce a ternary complex when combined with HepG2 nuclear extracts or recombinant human Sp1. C/EBP alpha was unable to substitute for C/EBP beta in forming this ternary complex. A poor C/EBP binding site is present adjacent to the Sp1 site, and mutagenesis of this site abolished formation of the ternary complex with the CYP2D5 regulatory region. These result establish that two transcription factors can work in conjunction, possibly by protein-protein interaction, to activate the CYP2D5 gene.

Maximal Activity of the Luteinizing Hormoneβ-Subunit Gene Requires β-Catenin

2007 ◽  
Vol 21 (4) ◽  
pp. 963-971 ◽  
Author(s):  
Travis B. Salisbury ◽  
April K. Binder ◽  
Jean C. Grammer ◽  
John H. Nilson
Keyword(s):  
Regulatory Region ◽  
Wnt Signaling Pathway ◽  
Maximal Activity ◽  
Early Gene ◽  
Orphan Nuclear Receptor ◽  
Functional Interaction ◽  
Reporter Assays ◽  
Transcriptional Complex ◽  
Canonical Wnt ◽  
Interfering Rna

Abstract GnRH regulates expression of LHB via transcriptional regulation of early growth response 1 (EGR1), an immediate early gene that encodes a zinc-finger DNA-binding protein. EGR1 interacts functionally with the orphan nuclear receptor steroidogenic factor 1 (SF1) and pituitary homeobox 1, a member of the paired-like homeodomain family. The functional synergism of this tripartite interaction defines the maximal level of LHB transcription that can occur in response to GnRH. Results presented herein provide new evidence that the interaction between SF1 and EGR1 also requires β-catenin, a transcriptional coactivator and member of the canonical Wnt signaling pathway. For instance, targeted reduction of β-catenin attenuates activity of a GnRH-primed LHB promoter. Additional gene reporter assays indicate that overexpression of β-catenin, or its targeted reduction by small interfering RNA, modulates activity of both SF1 and EGR1 as well as their functional interaction. β-Catenin coimmunoprecipitates with SF1. Moreover, an SF1 mutant that lacks a β-catenin binding domain has compromised transcriptional activity and fails to interact synergistically with EGR1. Finally, GnRH promotes β-catenin colocalization with SF1 and EGR1 on the endogenous mouse Lhb promoter-regulatory region. Taken together, these data suggest that β-catenin binds to SF1 and that this interaction is required for subsequent functional interaction with EGR1. Thus, these data identify β-catenin as a new and required member of the basal transcriptional complex that allows the LHB promoter to achieve maximal activity in response to GnRH.

scholarly journals Multiple Epitopes in the Murine Cytomegalovirus Early Gene Product M84 Are Efficiently Presented in Infected Primary Macrophages and Contribute to Strong CD8+-T-Lymphocyte Responses and Protection following DNA Immunization

2004 ◽  
Vol 78 (20) ◽  
pp. 11233-11245 ◽  
Author(s):  
Ming Ye ◽  
Christopher S. Morello ◽  
Deborah H. Spector
Keyword(s):  
T Cells ◽  
T Cell ◽  
Antigen Presentation ◽  
T Cell Responses ◽  
Dna Vaccination ◽  
Early Gene ◽  
Murine Cytomegalovirus ◽  
Specific Response ◽  
Mcmv Infection ◽  
Cell Responses

ABSTRACT We previously demonstrated that after vaccination of BALB/c mice with DNA encoding murine cytomegalovirus (MCMV) IE1 or M84, a similar level of protection against MCMV infection was achieved. However, the percentage of antigen-specific CD8+ T cells elicited by IE1 was higher than that by M84 as measured by intracellular cytokine staining when splenocytes were stimulated with an epitope peptide (M. Ye at al., J. Virol. 76:2100-2112, 2002). We show here that after DNA vaccination with M84, a higher percentage of M84-specific CD8+ T cells was detected when splenocytes were stimulated with J774 cells expressing full-length M84. When the defined M84 epitope 297-305 was deleted, the mutant DNA vaccine was still protective against MCMV replication and induced strong M84-specific CD8+-T-cell responses. The M84 gene was subsequently subcloned into three fragments encoding overlapping protein fragments. When mice were immunized with each of the M84 subfragment DNAs, at least two additional protective CD8+-T-cell epitopes were detected. In contrast to strong responses after DNA vaccination, M84-specific CD8+-T-cell responses were poorly induced during MCMV infection. The weak M84-specific response after MCMV infection was not due to poor antigen presentation in antigen-presenting cells, since both J774 macrophages and primary peritoneal macrophages infected with MCMV in vitro were able to efficiently and constitutively present M84-specific epitopes starting at the early phase of infection. These results indicate that antigen presentation by macrophages is not sufficient for M84-specific CD8+-T-cell responses during MCMV infection.

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